Mold for forming an optical fiber connector

ABSTRACT

A mold for molding optical fiber connector includes a core pin, a cavity mold and a sprue hole defined on the sidewall of the cavity mold. The core pin is used to mold the blind hole of the optical fiber connector. The cavity mold and the core mold cooperatively define a molding cavity for forming the optical fiber connector. A support block is configured in the molding cavity. The molding cavity includes a lens forming portion used to mold the lens and the support block configures a cutout to support the blind hole forming portion to make the blind hole forming portion align with the lens forming portion during the molding process, the opening of the cutout is towards the sprue hole.

BACKGROUND

1. Technical Field

The present disclosure relates to molds, and particularly, to a mold forforming an optical fiber connector.

2. Description of Related Art

Optical fiber connectors typically include a lens and a blind holebehind the lens. The blind hole receives an optical fiber. The lensreceives and guides light from the optical fiber. The alignment accuracybetween the blind hole and the lens is very important to the opticaltransmission ability of the optical fiber connectors.

Injection molding is a current molding method for molding optical fiberconnectors. The mold used in injection molding includes a core pin usedto mold the blind hole and a lens forming portion corresponding with thecore pin. During the injection molding process, the core pin must keepalignment with the lens forming portion to make sure the alignmentaccuracy between the blind hole and the lens of the molded optical fiberconnector.

However, the longitudinal axis of the blind hole usually deviates froman optical axis of the lens in the optical fiber connector mold by theabove-mentioned method. The main reason is that the impact of themolding material during the molding process causes the core pin to bend,thus causing the longitudinal axis of the core pin inclination relativeto the central axis of the lens forming portion (the central axis of thelens forming portion coincides with the optical axis of the moldedlens).

Therefore, a mold for molding optical fiber connectors, which canovercome the above-mentioned problems, is needed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded view of a mold for molding an optical fiberconnector, according to the first embodiment.

FIG. 2 is an assembled view of the mold of FIG. 1.

FIG. 3 is a sectional view taken along line of the mold of FIG. 2.

FIG. 4 is a schematic view of the cavity mold of a mold for molding anoptical fiber connector, according to the second embodiment.

FIG. 5 is a schematic view of the cavity mold of a mold for molding anoptical fiber connector, according to the third embodiment.

DETAILED DESCRIPTION

Referring to FIGS. 1 to 3, a mold 100, according to the firstembodiment, molds an optical fiber connector (not shown). The opticalfiber connector includes blind holes and lenses.

The mold 100 includes a core mold 10, a cavity mold 20 and two core pins30. The core pin 30 includes an insertion portion 31 and a blind holeforming portion 32. The blind hole forming portion 32 is used to moldthe blind hole of the optical fiber connector.

The cavity mold 20 and the core mold 10 cooperatively define a moldingcavity 21 for forming the optical fiber connector. The molding cavity 21includes a support surface 22. The support surface 22 defines two lensforming portions 221. The lens forming portion 221 is used to form thelens of the optical fiber connector. After the mold 100 is assembled,the insertion portion 31 of the core pin 30 is fixed by the core mold 10and the blind hole forming portion 32 of the core pin 30 stretches intothe molding cavity 21 and aligns with the lens forming portion 221.

In the sidewall of the cavity mold 20, a sprue hole 40 is defined and isin communication with the molding cavity 21 to allow molding material togo into the molding cavity 21. In present embodiment, the central axisof the sprue hole 40 is substantially perpendicular with thelongitudinal axis of the core pin 30. It is to be understood that inalternative embodiment, the central axis of the sprue hole 40 may be notperpendicular with the longitudinal axis of the core pin 30.

The cavity mold 20 also includes two support blocks 231 in the moldingcavity 21, corresponding with the two lens forming portions 221. Eachsupport block 231 defines a V-shaped cutout 232 to support the blindhole forming portion 32 to make the blind hole forming portion 32 alignwith the corresponding lens forming portion 221 during the moldingprocess. The opening of the cutout 232 is set towards the sprue hole 40.In alternative embodiments, the number of the support block 231 may bedifferent and depends on the number of the blind holes of the opticalfiber connector molded by the mold 100. When the number of the supportblocks 231 is more than one, the opening of the cutout 232 defined oneach support block 231 must be set towards the sidewall which definesthe sprue hole 40. Furthermore, the opening of the cutout 232 defined oneach support block 231 must be set towards the sprue hole 40.

During the process of molding optical fiber connector using the mold100, the high-speed molding material flow is injected through the spruehole 40 into the molding cavity 21 and impacts the blind hole formingportion 32 supported by the cutout 232 of the support block 231. Thedirection of the impact force applied on the blind hole forming portion32 substantially along the direction of the connection line from thesprue hole 40 to the support block 231. By setting the direction of theopening of the cutout 232 towards the sprue hole 40, the support force Foffered by the cutout 232 opposite to the direction of the impact forceto cancel the impact force. Thus, the alignment accuracy between thelongitudinal axis of the blind hole and the optical axis of the lens inthe optical fiber connector molded by the mold 100 is improved.

The core mold 10 includes a containing chamber 11 and a block 12 mountedin the containing chamber 11. The block 12 defines two holes 13corresponding with the two lens forming portions 221 of the cavity mold20. The hole 13 is used to hold the insertion portion 31 of the core pin30. In present embodiment, the hole 13 is a blind hole. It is to beunderstood that in alternative embodiments, the holes 13 may be athrough hole and the number of the holes 13 may be different and dependson the pattern of the optical fiber connector molded by the mold 100.

FIG. 4 shows a cavity mold 200 of the mold according to a secondembodiment. The cavity mold 200 is similar to the cavity mold 20 of thefirst embodiment except that the sprue hole 202 is defined in thesidewall of the cavity mold 200. Of course, the direction of the openingof the cutout 201 also towards the sprue hole 202.

FIG. 5 shows cavity mold 300 according to a third embodiment. Thecutouts 301 are U-shaped and the opening of the cutouts 301 is settowards the sprue hole 302. It is to be understood that in alternativeembodiments, the shape of the cutout can be different.

It is to be understood, however, that even though numerouscharacteristics and advantages of the present embodiments have been setforth in the foregoing description, together with details of thestructures and functions of the embodiments, the disclosure isillustrative only, and changes may be made in detail, especially inmatters of shape, size, and arrangement of parts within the principlesof the disclosure to the full extent indicated by the broad generalmeaning of the terms in which the appended claims are expressed.

1. A mold for forming an optical fiber connector which includes a blindhole and a lens aligned with the blind hole, the mold comprising: a corepin including an insertion portion and a blind hole forming portion; acore mold defining a hole for receiving the insertion portion; and acavity mold attached to the core mold, the cavity mold and the core moldcooperatively defining a molding cavity for forming the optical fiberconnector, the cavity mold including a lens forming portion in themolding cavity, the core pin aligned with the lens forming portion andthe blind hole forming portion thereof exposed in the molding cavity,the cavity mold comprising a support block in the molding cavity, and asprue hole communicating with the molding cavity, the sprue holeconfigured for introducing molding material in the molding cavity, acutout defined in the support block and configured for retaining theblind hole forming portion and maintaining alignment between the corepin and the lens forming portion, the cutout opening toward the spruehole.
 2. The mold of claim 1, wherein a central axis of the sprue holeis perpendicular to the longitudinal axis of the core pin.
 3. The moldof claim 1, wherein the cutout has a V-shaped cross-section.
 4. The moldof claim 1, wherein the cutout has a U-shaped cross-section.